Answer:
68,2%
Explanation:
Supposing the initial salt concentration of lake Parsons is the same of non-isolated lakes, 6,67L, and the change of salt concentration in isolated lake is just for water evaporation it is possible to write:
6,67gL⁻¹×X = 21gL⁻¹×Y
<em>-Where X is the initial water and Y is the water that remains in the isolated lake-</em>
Thus:
6,67X = 21Y
0,318 = Y/X
0,318 is the ratio of water that remains between total water. To obtain the ratio of evaporated water:
1-0,318 = 0,682
In percentage: <em>68,2%</em>
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I hope it helps!
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Answer:
48 g/mol
Explanation:
Step 1: Calculate the mass of the gas (m)
According to the law of conservation of mass, the mass of the solid before the decomposition must be equal to the sum of the masses of the solid residue and the gas
mSolid = mResidue + mGas
mGas = mSolid - mResidue = 4.73 g - 4.10 g = 0.63 g
Step 2: Convert 320 cm³ to L
We will use the conversion factor 1 L = 1000 cm³.
320 cm³ × 1 L/1000 cm³ = 0.320 L
Step 3: Calculate the moles of gas (n)
The gas is at room temperature (298.15 K) and room pressure (1 atm). We can calculate the moles of gas using the ideal gas equation.
P × V = n × R × T
n = P × V/R × T
n = 1 atm × 0.320 L/(0.0821 atm.L/mol.K) × 298.15 K = 0.0131 mol
Step 4: Calculate the molecular mass of the gas (M)
We will use the following expression.
M = m/n = 0.63 g/0.0131 mol = 48 g/mol
Answer:
Explanation:
Hello,
In this case, by considering the mathematical definition of by mass percentage of a solute as shown below:
We are able to compute the mass of the solute in a 20% solution having 500 g of solution as follows:
Best regards.
Answer// I’m pretty sure it’s A!
Explanation:
it allows scientists from disparate regions to use a single standard in communicating scientific data without vocabulary confusion.
